ACR Y DSCNT TO OCCUPIED ALT HAD LTSS FROM ATX X. SYS ERROR.

Narrative

D SIDE WAS COMBINED WITH RADAR AT THE MARION POS. ATX X WAS ISSUED A CLRNC DIRECT TO ROD VOR. HIS COURSE WOULD KEEP HIM CLR OF THE MNN SECTORS. ZID TOOK THE HDOF ON THE ACFT; THEN LATER DECIDED THEY WOULD NOT TAKE THE ACFT ON THAT COURSE. SO ATX X WAS PUT ON A HDG TO JOIN V72 INSIDE MNN SECTOR AIRSPACE. ZID WAS UNABLE TO HAND THE ACFT BACK TO ZOB; THE ACFT DROP FROM ZOB TRACK. ANOTHER TRACK HAD TO BE STARTED. SINCE THE D SIDE CTL POS HAD PREVIOUSLY BEEN COMBINED WITH THE RADAR; ALL COORD WAS GOING ON WITH ZID AND MNN RADAR CTLR. ACR Y WAS ON A NW HDG S OF MFD; ALSO GOING TO ROD. AFTER A COUPLE OF RADAR UPDATES PAST MFD THE ACFT WAS STILL NWBOUND. I THEN TURNED THE ACFT DIRECT ROD WITH A DSCNT FROM FL200 TO 14000 FT. TAKING INTO ACCOUNT THE TURN AND DSCNT RATE OF THE ACFT I ASSUMED THESE ACFT WOULD NOT BE IN CONFLICT AND TURNED MY ATTN TO THE D SIDE FUNCTIONS. ACR Y MADE A TIGHTER TURN THAN EXPECTED AND CAUGHT UP TO ATX X. ACR Y WAS TURNED TO A HDG 330 DEGS; WHICH THE PLT QUESTIONED; BUT THEN TURNED. ATX X WAS TURNED TO A 180 DEG HDG.